The value of hydrocarbons can often be enhanced by alkylation of lower hydrocarbons to produce higher molecular weight hydrocarbons. For example, isobutanes can be alkylated with isobutene to produce isooctane, which is valuable for increasing the octane rating of gasoline. A common commercial method for alkylating a hydrocarbon is to react the hydrocarbon with selected olefins in the presence of a strong acid, such as sulfuric acid. Unfortunately, such acid, solutions are not readily miscible with organic liquids. Consequently, in alkylation processes catalyzed by strong acids, it has been necessary to use a considerable excess of acid to effect a commercially feasible degree of alkylation. The unused acid is discarded with the spent acid, thereby reducing the efficiency of the process and augmenting the already burdensome waste disposal problem. Improvements which will reduce the amount of acid waste have long been sought.